Most modern automotive fuel systems utilize fuel injectors to deliver fuel to the engine cylinders for combustion. The fuel injectors are mounted on a fuel rail to which fuel is supplied by a pump. The pressure at which the fuel is supplied to the fuel rail must be metered to ensure the proper operation of the fuel injectors. Metering is carried out using pressure regulators that control the pressure of the fuel in the system at all engine r.p.m. levels.
Referring to FIG. 5, there is illustrated a known flow-through type pressure regulator 10 having a first cup shaped cover 12 and a second cup shaped cover 14 that are crimped together to form an unitary hollow member. In the axially aligned center of the enclosed end 16 of the first cover 12 is an outlet port 18 wherein fuel flows out of the regulator 10. Around the bottom 20 of the enclosed end 22 of the second cover 14 is located at least one fuel inlet aperture 24 for receiving fuel into the regulator 10.
The known flow-through type pressure regulator includes a bias means such as a spring 30 that functions to bias a valve seat member 36 of the regulator 10 at a predetermined amount of pressure that relates to the pressure desired by the regulator. One end of the spring 30 is located in a spring retainer 34 that is secured to a portion of the valve seat member 36 that extends through a central aperture 38 in a diaphragm 40. The diaphragm 40 is supported around its circumference on a circumferential flange 42 radially extending from the open end 44 of the second cover 14 and is crimped between a circumferential flange 46 extending radially outward of the open end 48 of the first cover 12. At the enclosed end 22 of the second cover 14 is a valve 50 that is secured to the second cover 14.
According to the known flow-through pressure regulator, the spring retainer is staked to the valve seat member 36. It is believed that the known flow-through type pressure regulator, as well as other types of pressure regulators, suffer from a number of disadvantages including a manufacturing process that requires additional assembly operations as well as tooling to perform the staking.
Thus, it is believed that there is a need to provide pressure regulators, e.g., of the flow-through and by-pass valve types, that overcome the disadvantages of the known pressure regulators.